盐胁迫对蓖麻Na^+、K^+吸收分布和叶绿素荧光的影响

Absorption and Distribution of Na+,K+ and Chlorophyll Fluorescence in Castor under Salt Stress

[目的]探讨蓖麻的耐盐机制。[方法]比较了栽培蓖麻淄蓖6号和天然生长于滨海盐碱地的野生蓖麻体内K+、Na+的分布特点、叶绿素荧光参数、植株生长状况和叶片渗透调节能力对NaC l处理的响应。[结果]野生蓖麻较栽培蓖麻具更明显的喜盐特性;蓖麻的耐盐机制在于促进K+的吸收和向地上部的运输,进而维持叶片的K+/Na+平衡;通过维持光系统Ⅱ的稳定性进而维持盐胁迫下叶片的光合速率。[结论]该研究为蓖麻在盐碱滩涂地的推广应用提供了理论依据。

[ Objective] The aim of this study is to reveal the salt resistance of castor. [ Method] Under salt stress, the growth, osmotic potential, chlorophyll fluorescence parameters, Na^ ＋ and K^＋ uptakes and transports in the seedlings of two Ricinus communis varieties （ cuhivar castor Zibi 6 and wild castor which grew naturally in coastal saline-alkali land） were comparatively studied. [ Result] Wild castor preformed better in halophilism than that of cuhivar castor Zibi 6 under the NaC1 treatment. One of the salt tolerant mechanisms of castor is to improve K ^＋ uptake and transport to overground portion, thus to maintain K ^＋/Na ^＋ homeostasis in leaves; on the other hand, the high stability of Photoreactian System 1I （PS II） plays a key role in maintaining the leaf photosynthetic rate under salt stress. [ Conclusion] The results of this study provided theoretical basis for the extension and application of castor in saline beach.